When five planets align

Rizal Park promenaders witnessed a special kind of show last May 5. No, it was not the regular Concert At The Park held every Sunday at the Open Air Auditorium. Neither was it the Santacruzan that signaled the Maytime festival at the park.

The occasion was the first-ever astronomical observation held at Luneta Boardwalk right at the back of Quirino Grandstand organized by the Philippine Astronomical Society (PAS), in cooperation with the Philippine Tourism Authority.

Promenaders witnessed the grand parade of planets, known to astronomers as planetary alignment, a world-class pageantry, literally.

The planetary alignment actually started in early January 2002, when Jupiter, Saturn, Mars and Mercury were in favorable view in the evening twilight. Mercury disappeared in the third week of January, while Venus emerged from the twilight glow in late-February. In late-April and early-May, during Mercury’s best appearance of the year, all five naked-eye planets were visible simultaneously in the western sky.

The astronomical observation last May 5 started as early as 4 p.m. when PAS members arrived and set up their telescopes.

Using solar filters, the budding astronomers were able to observe the disc of the Sun and the sunspots. They were also given an impromptu lecture by PAS members about how sunspots were formed.

After the Sun set at about 5:30, the number of observers swelled from a hundred to an unbelievable thousands of spectators of all ages.

They, too, hunted for the first bright "star" that came out in the afternoon twilight. The bright star was actually the planet Venus, the brightest object in the evening sky next only to the Moon!

It was followed by the brightest star Sirius in the constellation Canis Major. Then came the planets Jupiter, that was almost directly above the zenith, Saturn, Mars, and unexpectedly, the elusive planet Mercury about to set in the western horizon.

Venus, Saturn and Mars formed a beautiful triangle formation a little above the horizon. This formation is a very rare planetary formation that will not be repeated until the year 2060.

The Luneta skywatchers were more than fortunate because they saw the planet Mercury. Because it is always hidden by the glare of the Sun, Mercury is seldom seen by the naked eye.

It was almost 8 p.m. when Venus, Saturn and Mars set in the western horizon. But there were still a number of spectators who were forming a line to see Jupiter and two of its four Galilean moons.

But we had to cap the night.

On Wednesday, the five planets will align again to form an almost straight line as seen in the evening twilight in the western sky. In addition, the crescent Moon will join the alignment, in between Venus and Jupiter.

PAS members will be at the Luneta Boardwalk on this day starting at 4 p.m. to give public lectures and offer free use of their telescopes. Everybody is invited.

(The author is a member of the Philippine Astronomical Society. He can be contacted at 0919-8558080. The PAS is at http://www.geocities.com/philastrosoc.)